Porous MnF2 with micro-nanostructures coated by a nitrogen doped carbon shell as an anode for enhanced lithium storage

Abstract

MnF2, an intriguing anode material for lithium-ion batteries (LIBs), has garnered significant attention due to its high theoretical capacity. However, its commercial viability is impeded by issues such as volume expansion and poor conductivity. In this study, we present the development and fabrication of MnF2@NC microspheres with micro-nanostructured pores, comprising MnF2 nanoparticles encapsulated within a nitrogen-doped carbon shell. This was achieved through a combination of hydrothermal synthesis and fluorination techniques. The MnF2@NC composite exhibits a high level of porosity, effectively mitigating the significant volume expansion of MnF2 and facilitating efficient charge transport. Moreover, the incorporation of nitrogen-doped carbon shell enhances the overall structural and promotes electrical conductivity. Leveraging these inherent characteristics, the MnF2@NC electrode demonstrates exceptional electrical conductivity and superior long-term stability. The MnF2@NC electrode serves as an anode for LIBs, exhibiting a remarkable reversible capacity of 991.2 mAh/g at 0.1 A/g, exceptional cycle performance with a capacity retention of 872.2 mAh/g after 700 cycles at 1.0 A/g, and outstanding rate capability surpassing the reported outcomes of MnF2-based composite anodes. These results unequivocally demonstrate the suitability and potential applicability of MnF2@NC as high-capacity anodes for LIB.